Have you enable the replies notification in your profile?
You can do this by clicking "Profile." Then go to your Preferences. Go down to "Always notify me of replies" and choose yes if you already haven't.
This option allows notifications sent to your email from every topic you have made/replied to.
If you want to be emailed for replies from a certain topic, just go down to the bottom of the topic and click "Watch this topic for replies."
I'm locking this topic now. If you have any further questions, feel free to PM me of any of the other staff members.